The Poinciana Flats (3522 Reading Road, Cincinnati) is a 1908, Queen Anne style, four-story Streetcar Suburb Apartment Building executed as a Court Apartment Building subtype. The building features an irregular U-shaped plan and a deep, narrow courtyard. Built of brick bearing masonry on a high ashlar limestone foundation laid in random courses with wood floor-framing, the Poinciana holds 44 apartments of similar layout.

The variegated orange-brown brick exterior features a corbelled brick cornice, darker brick quoins and angled turrets at the corners that reflect a Romanesque Revival influence. The Poinciana is located in the South Avondale neighborhood of Cincinnati, prominently sited at the northeast corner of Reading Road and Hutchins Avenue. The courtyard is enclosed by an original ornamental iron fence on a limestone curb and gateway formed by square brick piers with limestone bases and caps. More recent iron fencing lines the concrete walkways through the courtyard to the three primary entrances. A surface parking lot is located to the rear of the building, accessible by Hutchins Avenue. The larger setting is mixed residential, commercial, surface parking lots and institutional buildings. Four other examples of suburban apartments stand nearby on Reading Road. Despite replacement of doors and windows, altered primary entries, and renovation of apartments, the building retains historic integrity.

As an example of a Streetcar Suburb Apartment, the Poinciana is significant for its role in providing multi-family living to middle-class residents in Avondale, an emerging inner-ring suburb that was in close proximity to public transport and shopping. As a Court Apartment, represents the evolution of multi-family, high-density residential buildings designed and located specifically to meet the housing needs of the growing numbers of middle-class residents during the early 20th century in the Avondale. It is also a material representation of the greatest construction boom of multi-family dwellings in Avondale, a broad trend that swept the United States from 1900 to 1965. Additionally, the Poinciana reflects the broad pattern of suburban development associated with Avondale's second major wave of construction associated with the migration of the Jewish middle-class from Cincinnati's West End to Avondale.

In 1869, the land on which the Poinciana was eventually built was owned by D. Gallup. Albert Barnes Voorheis, a banker, and Isaac Mack, a clothing manufacturer, recorded the Mack-Voorheis subdivision in 1892. Mack died in 1894, and the land was not transferred again until 1904, when Voorheis purchased Edgar Mack's share (Edgar was presumably a son, although not mentioned in Mack's obituary). The Hamilton County Auditor mistakenly lists the Poinciana's construction date as 1900. However, a 1904 Sanborn Fire Insurance map shows undeveloped land at the future site of the Poinciana. It is thought that the land was undeveloped until the construction of the Poinciana in 1908.

In 1889, streetcar routes began to be electrified. The Thompson Houston Company was hired to electrify the Avondale route in 1890 and built a generating station at the corner of Reading Road and McMillan to furnish power. C. S. Mendenhall's Standard Guide Map of Cincinnati, published in 1903, shows that the "Winton Place" route was already running along Reading Road. The combination of transportation improvements, a growing population, and annexations of outlying neighborhoods by the city spurred an exodus to the hilltops. As stated by History Professor David Stradling, "The electric streetcar not only reflected the growth of all of these more distant places, but also encouraged it. Streets with trolley lines developed more intensely than those without, as business districts and apartment buildings thrived on the easy access provided by the streetcars."

By the early 20th century this fast and inexpensive mode of transportation allowed less affluent residents to settle in newer, less expensive subdivisions in southern Avondale. Upper- and middle-class suburban apartments began to appear along Reading Road, a major thoroughfare in Avondale, specifically the Cumberland (808 Cleveland Avenue, 1890), a unique dumbbell-plan, six-flat apartment building (now clad in aluminum siding) and the Somerset (802-814 Blair Avenue, 1896), a 24-unit four-story Queen Anne style building designed by Joseph Steinkamp for the Emery brothers. These new developments resulted in a community development pattern shift away from large single family residences built on spacious lots to the construction of high density suburban apartment buildings.

The Poinciana is one of several upper- and middle-class Streetcar Suburb Apartments built around 1900 along Reading Road, a major streetcar artery in Avondale. The Poinciana reflects the evolution of multi-family residential buildings located specifically to meet the needs of the growing middle-class moving into Avondale. The Poinciana's location would have provided access to convenient and affordable transportation, shopping and services within a short walk. The streetcar would have accommodated residents as they commuted from work to home. The 1920 census indicates that the majority of the tenants that lived in the Poinciana were in the service sector; there were several stenographers, retailers and salesmen listed. As stated in the MPD, "Residents working in the newly expanding service sector were generally not well paid, so they sought inexpensive housing in areas of the city with easy access to public transportation." As a Streetcar Suburb Apartment, the Poinciana is significant for providing multi-family living to middle-class residents in Avondale, an emerging inner-ring suburb, that was in close proximity to public transport and shopping. In addition to the convenience of its location along the streetcar line, the Poinciana was sited on a prominent corner on the northern edge of Avondale's business district. A 1932 survey of Cincinnati's neighborhood business districts ranked Avondale as one of the city's "very best residential districts." With a population of 22,900, Avondale was thriving. By the late 1920s the business center, located along Reading Road near the intersection of Rockdale Avenue, had 41 businesses located between Windham and Hutchins Avenues.

The Poinciana reflects the broad pattern of suburban development associated with the migration of the Jewish population from Cincinnati's West End to Avondale. The Poinciana, and other suburban apartment buildings, provided housing for the growing Jewish middle-class in Avondale, allowing the community to become more diverse. These new residents included many Eastern European Jews, particularly following a general exodus of the Jewish population from the declining West End in the early twentieth century, would profoundly change the character of the community. Between the 1920s and the end of World War II, Avondale was known as the "gilded ghetto," with Jewish inhabitants making up 60% of the suburb's total population. A variety of Jewish institutions and businesses, many of which originated in the old Jewish neighborhoods of the West End, also took up residence in Avondale at this time. The Poinciana is a physical reminder of Avondale's transition from an upper-class suburb to a more architecturally and socio-economically diverse neighborhood.

After World War II, the community development pattern and the population began to transition as the Jewish community began to move out of Avondale to Amberley Village. Through the 1950s, 60s and 70s property values continued a downward spiral as land use patterns changed and density increased substantially in Avondale. It became common for the large single family dwellings to be subdivided into apartments. In addition to the subdivision of dwellings, the increase of renter-occupied housing resulted from the development of vacant land zoned for high-density apartment development, which changed the community development pattern as green space on residential side streets were replaced with large multi-unit apartment buildings. After the Krug Realty Company sold the Poinciana in 1967, the property transferred eleven times before the current owners purchased the property in 2012.

The Poinciana, built before the proliferation of motor vehicles, is significant within its historic contexts for its role in providing multi-family living to middle-class residents in an emerging inner ring suburb that was in close proximity to public transport and shopping. With the discontinuation of the streetcar system, Avondale ceased being a streetcar suburb. The discontinuation of the "Winton Place" route in 1949 marks the closing date of the Poinciana's period of significance, as the era in which it was conceived and constructed came to an end.